package com.hsoft.zhxy.common.util;

import javax.crypto.*;
import javax.crypto.spec.SecretKeySpec;
import java.io.UnsupportedEncodingException;
import java.security.InvalidKeyException;
import java.security.NoSuchAlgorithmException;
import java.security.SecureRandom;
import java.util.Base64;


/**
 * AES加密算法 与EncrypAES的区别为，需要传入一个固定的字符串，而非一个随机的字符串作为密钥
 * 与CryptUtil的区别为，AES加密、解密(linux、window加密解密效果一致,支持中文)
 *
 * @author xxh
 */
public class EncryAESUtils {
    private static int length = 128;

    private static String key = "HITxinxiban";

    /**
     * 加密
     *
     * @param content  需要加密的内容
     * @param password 加密密码
     * @return
     * @throws NoSuchAlgorithmException
     * @throws NoSuchPaddingException
     * @throws UnsupportedEncodingException
     * @throws InvalidKeyException
     * @throws BadPaddingException
     * @throws IllegalBlockSizeException
     */
    private static byte[] encrypt(String content, String password) throws Exception {

        KeyGenerator kgen = KeyGenerator.getInstance("AES");
        SecureRandom secureRandom = SecureRandom.getInstance("SHA1PRNG");
        secureRandom.setSeed(password.getBytes());
        kgen.init(length, secureRandom);
        SecretKey secretKey = kgen.generateKey();
        byte[] enCodeFormat = secretKey.getEncoded();
        SecretKeySpec key = new SecretKeySpec(enCodeFormat, "AES");
        Cipher cipher = Cipher.getInstance("AES");// 创建密码器
        byte[] byteContent = content.getBytes("utf-8");
        cipher.init(Cipher.ENCRYPT_MODE, key);// 初始化
        byte[] result = cipher.doFinal(byteContent);
        return result; // 加密

    }

    /**
     * 解密
     *
     * @param content  待解密内容
     * @param password 解密密钥
     * @return
     */
    private static byte[] decrypt(byte[] content, String password) throws Exception {

        KeyGenerator kgen = KeyGenerator.getInstance("AES");
        SecureRandom secureRandom = SecureRandom.getInstance("SHA1PRNG");
        secureRandom.setSeed(password.getBytes());
        kgen.init(length, secureRandom);
        SecretKey secretKey = kgen.generateKey();
        byte[] enCodeFormat = secretKey.getEncoded();
        SecretKeySpec key = new SecretKeySpec(enCodeFormat, "AES");
        Cipher cipher = Cipher.getInstance("AES");// 创建密码器
        cipher.init(Cipher.DECRYPT_MODE, key);// 初始化
        byte[] result = cipher.doFinal(content);
        return result; // 加密

    }

    // /**
    // * 将二进制转换成16进制
    // *
    // * @param buf
    // * @return
    // */
    // public static String parseByte2HexStr(byte buf[]) {
    // StringBuffer sb = new StringBuffer();
    // for (int i = 0; i < buf.length; i++) {
    // String hex = Integer.toHexString(buf[i] & 0xFF);
    // if (hex.length() == 1) {
    // hex = '0' + hex;
    // }
    // sb.append(hex.toUpperCase());
    // }
    // return sb.toString();
    // }
    //
    // /**
    // * 将16进制转换为二进制
    // *
    // * @param hexStr
    // * @return
    // */
    // public static byte[] parseHexStr2Byte(String hexStr) {
    // if (hexStr.length() < 1)
    // return null;
    // byte[] result = new byte[hexStr.length() / 2];
    // for (int i = 0; i < hexStr.length() / 2; i++) {
    // int high = Integer.parseInt(hexStr.substring(i * 2, i * 2 + 1), 16);
    // int low = Integer.parseInt(hexStr.substring(i * 2 + 1, i * 2 + 2),
    // 16);
    // result[i] = (byte) (high * 16 + low);
    // }
    // return result;
    // }

    /**
     * 加密
     *
     * @param content  需要加密的内容
     * @param password 加密密码
     * @return
     */
    public static byte[] encrypt2(String content, String password) {
        try {
            SecretKeySpec key = new SecretKeySpec(password.getBytes(), "AES");
            Cipher cipher = Cipher.getInstance("AES/ECB/NoPadding");
            byte[] byteContent = content.getBytes("utf-8");
            cipher.init(Cipher.ENCRYPT_MODE, key);// 初始化
            byte[] result = cipher.doFinal(byteContent);
            return result; // 加密
        } catch (NoSuchAlgorithmException e) {
            e.printStackTrace();
        } catch (NoSuchPaddingException e) {
            e.printStackTrace();
        } catch (InvalidKeyException e) {
            e.printStackTrace();
        } catch (UnsupportedEncodingException e) {
            e.printStackTrace();
        } catch (IllegalBlockSizeException e) {
            e.printStackTrace();
        } catch (BadPaddingException e) {
            e.printStackTrace();
        }
        return null;
    }

    public static String encrypt2Str(String content, String password) throws Exception {
        byte[] encryptResult = encrypt(content, password);
        return Base64.getEncoder().encodeToString(encryptResult);
    }

    public static String decrypt2Str(String content, String password) throws Exception {
        byte[] decryptResult = decrypt(Base64.getDecoder().decode(content), password);
        return new String(decryptResult, "UTF-8");
    }

    public static String decrypt2Str(String content) {
        try {
            return decrypt2Str(content, key);
        } catch (Exception e) {
            e.printStackTrace();
        }
        return content;
    }

    public static String encrypt2Str(String content) {
        try {
            return encrypt2Str(content, key);
        } catch (Exception e) {
            e.printStackTrace();
        }
        return content;
    }

    public static void main(String[] args) throws Exception {
//        if (args.length == 0) {
//            System.out.println("没有获取到输入的参数");
//        } else {
//            String content = "t太阳est地";
//            // 加密
//            System.out.println("加密前：" + content);
//
//            String tt4 = encrypt2Str(content);
//            System.out.println(new String(tt4));
//
//            // 解密
//            String d = decrypt2Str(tt4);
//            System.out.println("解密后：" + d);

        // 加密前：t太阳est地
        // Bpf0jyJDj/pVHaRf66+OMA==
        // 解密后：t太阳est地
        System.out.println();

    }

    public static int ack(int m, int n) {
        if (m == 0) {
            return n + 1;

        } else if (n == 0) {
            return ack((m - 1), 1);
        } else {
            return ack((m - 1), ack(m, (n - 1)));
        }

    }

    public int maxArea(int[] height) {
        //利用贪心算法
        //在这里容积就是面积，它受长和高的影响，当长度减小的时候，只能增大高才有可能提升面积，所以我们从长度最长时开始递减，然后用更高的线来补齐

        int max_area = 0;
        int max_temp = 0;
        int min_height = 0;
        int start = 0, end = height.length - 1;
        for (; start < end; ) {
            min_height = height[start] < height[end] ? height[start] : height[end];
            max_temp = (end - start) * min_height;
            if (max_temp > max_area) {
                max_area = max_temp;
            }
            if (height[start] > height[end]) {
                end--;
            } else {
                start++;
            }
            // if(height[start]<=height[end]){
            //这样不行的主要原因是因为上面比较后，如果end减一这个时候此时这个又会比较一次但是还没有计算这个上面end--的容积。每次只能比较一次。
            //     start++;
            // }
        }
        return max_area;
    }

}
